Reconstructed baryon transition current structure of the N(1520) longitudinal amplitude via selective expansion: Insights from Patterson function analysis

A model-independent reconstruction of the transition current density associated with the N(1520) longitudinal amplitude is presented using Patterson function analysis combined with a selective expansion procedure. The method was developed to improve agreement between the reconstructed profile and the empirical Patterson distribution while preserving the principal nodal structure of the transition current. The resulting density exhibits a strongly localized positive core surrounded by a negative shell, with a half-maximum radius of 0.0751 fm and zero crossings at 0.129 fm and 0.270 fm. Analysis of the corresponding r2ρ(r) distribution reveals that most of the transition-current strength is concentrated within a narrow spatial region. Comparison with previously reconstructed baryon transition currents shows that the N(1520) longitudinal amplitude possesses one of the most pronounced negative minima relative to its central peak, indicating a distinctive spatial organization. These results provide an empirical visualization of the internal transition-current structure associated with the N(1520) resonance and demonstrate the usefulness of selective expansion for enhancing Patterson-based reconstructions.